2005 XC90 2.5T chokes and stalls when warm

Shawnkaan · Post by **Shawnkaan** » 26 Oct 2015, 17:42

2005 XC90 2.5t P0243 and P0101. I replaced the MAF and still get the error codes. I can clear the codes and the motor runs strong until it heats up. Then it will choke and stall. It starts right up but dies right away until it cools down. I am at my wits end. I did just replace the motor and everything went very smooth. The other issue I see is that the thermostat is not opening up. I changed the thermostat to the one that was out of the older motor. (2nd cylinder in old motor had 60 LBS of compression and burned a ton of oil.) Any help is greatly appreciated and thank you in advance!!

Post by **cn90** » 26 Oct 2015, 20:21

- What brand is MAF? I use Bosch only.

- Tstat: use only new one made by Wahler, the ECT is already included in the package deal (tstat + housing + ECT).

Shawnkaan · Post by **Shawnkaan** » 03 Nov 2015, 10:24

I used a bosch MAF and the thermostat I used a beck/arnley thermo housing combo. I found a petcock on the back of the motor in the coolant lines that I tried to open and bleed the system. No luck. I left it running for about a half hour and the fans kick in, temp doesn't seem to get about half way on the dash. I checked with my thermogun and the block is about 230 degrees. The other thing I noticed is when its cool, i start it you can hear the turbo. Runs great... when it warms up the P0243 comes back and disables the turbo. As you step on the gas it pings. Any other area I should be looking? Should I replace the tiny waste gate solenoid A?

Post by **cn90** » 03 Nov 2015, 15:47

Don't know about Beck/arnley (they repackage stuff and resell), but the tstat combo also contains an ECT.

This ECT is very finicky, wrong Ohm values (it works on NTC principles) ---> engine stalls.

If I were you, I'd replace with known Wahler tstat (PN 31293698, about $100 at rmeuropean dot com) or Volvo OEM tstat.

Shawnkaan · Post by **Shawnkaan** » 19 Nov 2015, 09:05

Thank You for your replies... Everything now seems to be up and running but I am still a little concerned over the vacuum lines. I was wondering if anyone had a detail or knowledge on the check valves and the flow direction? I am thinking maybe I reversed one when I changed all the vacuum lines. I found a great diagram under the hood but it doesn't show the direction or which way the arrow should be going on the check valve. Thanks in advance!